The fabrication of bicycle frames from fiber reinforced polymer composites is well known in the prior art. For example, the use of thermoset composites to fabricate bicycle frames is disclosed in U.S. Pat. Nos. 4,850,607 and 4,889,355. In particular, these references describe the fabrication of bicycle frames through the use of resin impregnated fibrous materials such as glass, KEVLAR, or carbon fiber. According to prior art fabrication methodology, these composite bicycle frames are typically constructed by first pre-forming the elongate, composite members thereof, and then interconnecting these members with composite joints.
For example, the prior art composite bicycle frame is typically fabricated by first forming a separate cross bar, down tube, and seat tube from a fiber reinforced polymer composite, and subsequently placing these components into a common fixture. The placement of the cross bar, down tube, and seat tube into the fixture maintains their desired orientations while they are connected to each other by forming interconnecting joints therebetween with additional fiber reinforced polymer composite material.
As will be appreciated by those skilled in the art, though this prior art fabrication methodology provides a bicycle frame which is lightweight and durable, it is extremely time consuming and expensive. In this respect, each of the interconnecting joints must be individually fabricated by hand. Further, extensive hand finishing to the frame is required such that a desirable smooth outer surface is provided.
Thus, although the prior art has recognized to a limited extent the benefits of providing a lightweight and durable bicycle frame, the known fabrication methodologies for such frames have been time consuming and cost ineffective. Accordingly, there exists a need in the prior art for a method of fabricating a composite bicycle frame which is lightweight and durable, wherein the method minimizes the manual operations involved in the practice thereof, and consequently facilitates the manufacture of the bicycle frame at a substantially reduced cost. In this respect, such a method requires the minimization or elimination of the prior art steps needed to provide the interconnection of the various frame components and for providing a desirable smooth overall finish to the frame so as to substantially reduce the amount of labor involved in the fabrication process.